Generally, a circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by overcurrent, overload or short circuits. The basic function of a circuit breaker is to interrupt current flow after protective devices (such as relays) detect a fault. Unlike a fuse, which operates once and then must be replaced, a circuit breaker can be reset to resume normal operation. Circuit breakers are made in varying sizes, from small devices that protect an individual household appliance up to large switchgears designed to protect high voltage circuits feeding an entire city.
Circuit breakers may be applied in various applications. For instance, circuit breakers are used in power stations for ensuring a reliable operation and a smooth delivery of current throughout the entire life of the power station. But also medium-voltage products play a pivotal role in the distribution part and embedded generation of the power value chain, facilitating the “last mile” connect that brings electricity to the users. Circuit breakers serve customers with a reliable, efficient, safe and sustainable technology that allows a much higher value package solution for specific customer needs.
CN205542211U relates to an insulator and a method of manufacturing the insulator having a silicon rubber-based weatherproof jacket fixed on outer surface of a wound pipe. On an inner side of the tubular wound pipe there is an inner liner attached. In an embodiment, the inner liner that is made of a plurality of adjacent tape elements such as fluoropolymer tapes.
U.S. Pat. No. 1,549,551A relates to a device for fastening the overlapping edges of flexible sheet insulating-material adapted to be bent into tubular form for the linings of switch tanks. It comprises a strip of insulating- material provided parallel to its edges with a number of staggered lugs arranged in a row that engage the edges of the sheet.
Circuit breakers provide a heating chamber for supporting the extinction of an electrical arc in the circuit breaker. For instance, the heating chamber may be a part of the arcing chamber of the circuit breaker. In the heating chamber, a gas may be heated by the electrical arc. The gas extinguishes the electrical arc, thereby avoiding damage to the electrical system of which the circuit breaker is part of. However, in the case of electrical arcs having a high intensity, the temperature in the heating chamber may rise to high degrees, such as up to 2000K (for a short time period). The pressure rise may be up to 5 bar/ms. Therefore, the heating chamber is protected by a heating chamber insulator. For instance, the heating chamber insulator may additionally include a PTFE layer for protecting the heating chamber.
The PTFE layer of the insulator body beneficially fulfills good insulating properties and withstands high mechanical stresses. The manufacturing of a PTFE layer with these demands is challenging. In known system, the PTFE layer can for instance be damaged at joining welds due to the high stress. Also, increasing the stability of the PTFE layer comes with additional costs.
In view of the above, a liner arrangement for an insulator body in a circuit breaker, a heating chamber insulator for a circuit breaker, and a method for protecting an insulator body of a heat chamber insulator for a circuit breaker are provided that overcome at least some of the problems in the art.